you will be more than susprirsed on staff travel. If you want to see just walk over to Asile A of hK Airport just to see what's there. And trust me 90% off the full fare J is still cheaper than some econ tickets.... and anacdotal evidences suggest to me most staff will try for J standby on longhaul, not for short haul.
I agree other possibility of DM upgrades etc etc but my own observations do suggest to me there are plenty on staff travel.